You may have noticed a new feature in AdSense ads this past week - variations in the number of text ads we show in any ad unit. We caught up with Brian A., a product manager for AdSense, to pick his brain about this new feature.

How have Google ads changed?

"We've updated AdSense to now vary the number of text ads that appear in a given ad unit. When we have a set of highly relevant and useful ads, we give them more of a presence in the ad unit by eliminating other ads. In some cases, if we determine a particular ad performs extremely well on a page, we'll remove all other ads from the unit and show just this single ad."

Sounds great for advertisers, but is this good for publishers?

"When we tested this feature, we saw that the increased user attention to these relevant ads resulted in a higher CTR. This means more revenue for publishers."

Is this good for a site's visitors?

"Definitely. The better-performing ads are more useful to users and this new feature gives them more presence in the ad unit. We are very careful to consider the user benefits with every feature so we can help our publishers grow their repeat traffic by showing more useful links on their pages."

Here's an example of an ad that has been expanded to fill an entire ad unit:

So don't be surprised if you see fewer ads taking up the same space in your ad units. Google AdSense technology will automatically determine the optimal number of ads to display on your pages and will only show fewer ads when doing so will increase your revenue.